TOP ROD®: Precision-Engineered Connecting Rods Since 1993

Founded in 1993 and headquartered in Taiwan, Chorng Ko IND. (TOP Rod®) is a premier manufacturer specializing in high-performance and long-lasting connecting rods. With nearly three decades of engineering excellence, we have become a trusted supplier for industry leaders such as SYM, KYMCO, AEON, and PGO.

Unrivaled Technical Expertise

Our capabilities span the entire product lifecycle—from feasibility assessment and material science research to advanced development and precision manufacturing. Whether it is a standard component or a highly complex customized project, our team delivers solutions tailored to the most demanding specifications.

To ensure world-class precision, our facility is equipped with state-of-the-art machinery and inspection tools sourced from Germany, Japan, and the USA.

Quality Without Compromise

As an ISO 9001:2015 certified company, quality is the cornerstone of our operations. We implement a rigorous, data-driven quality control system to ensure that every part leaving our floor is "second to none." This commitment to excellence has earned us a global reputation for reliability, competitive pricing, and exceptional customer service.

Diverse Market Solutions

From OEMs to the high-performance aftermarket, our products empower:

• Scooters & Motorcycles
• Outboard Engines & Marine Applications
• Modified Engines & Motocross Bikes
• Jetskis, Snowmobiles, ATVs, and UAVs

Notably, our proprietary fracture-splitting technique for marine conrods and snowmobile conrods is especially famous in this field, ensuring high-strength and lightweight designs.

Partner with Chorng Ko, TOP ROD®

We invite you to experience the TOP ROD ® difference. Contact us today to discuss how our engineering prowess can support your next project.

Extended Content: Production Processes - From Heavy Shaping to Micron Precision

Our facility employs a sophisticated, vertically integrated manufacturing process designed to deliver connecting rods with dimensional accuracy.

Advanced Shaping

The process begins with our 600-Ton Computer-aided Shaping Machine, which ensures robust initial forming of the rod blanks.

Precision Machining

Following this phase, components move to the CNC (Computer Numerical Control) Lathe and CNC Machine Center stations. The use of CNC technology allows Chorng Ko to handle high-variety and complex orders ranging from standard parts to high-performance modifications.

Heat Treatment

Most motorcycle connecting rods are forged from chromoly steel, specifically SCM415 (SAE 4115). As a low-carbon alloy, SCM415 requires carburizing heat treatment to achieve the necessary surface hardness. We believe that precision-controlled heat treatment is the critical process in optimizing connecting rod durability and performance.

Grinding and Honing Excellence

To achieve the mirror-like finishes and tight tolerances required for high-performance engine parts, we utilize Double-disc Vertical and Horizontal Grinding Machines to ensure perfectly parallel surfaces. Furthermore, our CNC-aided Bore Grinding and Honing Machines allow for the bore diameters of conrods to be refined to exact specifications, ensuring perfect fitment in assembly lines.

Extended Content: Quality Assurance: A Data-Driven Approach

The quality of TOP ROD® is defined by data, not just observation. The company’s Quality Control (QC) department operates on a foundation of Statistical Process Control (SPC) and Measurement Systems Analysis (MSA) to guarantee that every shipment meets the customer's requirements.